From what I remember when Uber did it, it usually involved some degree of theft or the breaking of someone's TOS or both and in this instance this seems like just good old fashioned competitive research.
There's a lawsuit b/c Lyft feels they can show that Uber actually caused monetary damages (and violated their TOS). If Knotel could do the same, they would also have a case. That's how civil law works. AFAIK, Uber wasn't accused of committing a crime in those instances.
WeWork apparently gave one of their customers 1 year free of charge to stop them from going to Knotel. I'm pretty sure they could "prove damages", too.
I don't think this counts as damages anymore than Burger King could sue McDonald's for damages for offering a coupon on Big Macs. Uber actually booked time and fake rides with competing services so they couldn't pick up legitimate riders.
A more apt comparison would be creating fake companies and renting out Knotel so a location fills up and real companies can't rent working space. Then never paying Knotel.